David Cameron will raise the issue of Neil Heywood's murder with senior Chinese officials, as pressure mounts on the Foreign Office to explain what it knew about the British businessman's death.

The prime minister is likely to discuss the case with Beijing's visiting propaganda chief, Li Changchun, on Tuesday, his spokeswoman said. "He [Cameron] will welcome the investigation that's ongoing and look forward to seeing the outcome of that," she said.

Li is the first senior Chinese official to visit Britain since it emerged this month that Gu Kailai, the wife of Bo Xilai, one of China's most powerful leaders, is suspected of murdering Heywood.

In Jakarta last week, Cameron promised British co-operation with the investigation and praised Chinese authorities for their decision to examine the "disturbing" case.

William Hague, the foreign secretary, is under pressure to explain why it took so long for Britain to raise the alarm after Heywood's murder. The businessman was found dead in his hotel room in the south-west city of Chongqing, and consular officials were informed on 16 November. Two months later the FCO asked China to investigate.

Hague is to give a statement on the case to the House of Commons on Tuesday. He is likely to face accusations that the FCO was slow off the mark because of a reluctance to offend Beijing and damage commercial ties. Several MPs have tabled questions, including the former Europe minister Denis MacShane and the former Liberal Democrat leader Menzies Campbell.

MacShane said he wanted to know what contacts Heywood had had with British diplomats, both at the consulate in Chongqing and at the Beijing embassy. He said the FCO should make public the information it had received from Wang Lijun, Bo's former chief of police. Wang fled to the US consulate in Chengdu and allegedly told US diplomats in February that Heywood had been poisoned.

MacShane said the sudden death of a well-connected Old Harrovian would not have reached the foreign secretary's desk but would have been noticed by diplomats in Chongqing. "When William Hague became foreign secretary, he decided to depoliticise the Foreign Office and turn it into a giant chamber of commerce. He has a pretty mercantalist approach to foreign policy." . He said the policy had not worked with China or Russia when British citizens got tangled up with powerful commercial or mafia interests.

Hague is also likely to face pressure to release cable traffic on Heywood between the British embassy in Beijing and London. "It's the old question that bedevilled Nixon: what did we know and when did we know it?" Campbell said.

He described the case as "shadowy" and said the true story of Heywood's murder may never emerge. Heywood had been an adviser for the private intelligence firm Hakluyt, founded by former officials with MI6, although the Foreign Office has discounted claims he was a spy. Campbell asked: "Was this man in any way part of British intelligence activity?"

The affair has already been politically embarrassing for the Foreign Office minister Jeremy Browne, who visited Chongqing on 15-16 November and had dinner with Bo Xilai, at a time when Heywood's body was being cremated without an autopsy.

Ministers only learned of the suspicious circumstances in February, the FCO said, after members of the British business community raised concerns. MacShane said he had some sympathy with Browne: "He's a tired minister, arriving tired from London. The worrying thing is that he wasn't properly briefed." .

Browne did not reply to messages asking him to comment.

• This article was amended on 17 April 2012. The original described Heywood as an associate with the private intelligence firm Hakluyt.